This is an executable type used in Stencila Schema for an individual message within a Chat.

It exists so messages can carry structured parts, execution state, attachments, and model-generated metadata rather than being reduced to plain text. This supports richer conversational documents and tooling for reviewing, replaying, or transforming model interactions.

Key properties include the message role, message parts or content, and inherited execution metadata from Executable.

This type is marked as unstable and is subject to change.

Analogues

The following external types, elements, or nodes are similar to a ChatMessage:

OpenAI chat message: Close analogue for role-based conversational turns, though Stencila messages can include block document content and attached files.

Anthropic message: Close provider-level analogue for structured chat turns.

Properties

The ChatMessage type has these properties:

Name	Description	Type	Inherited from
`author`	The author of the message	`Author`	-
`role`	The role of the message in the conversation.	`MessageRole`	-
`content`	The content of the message.	`Block`*	-
`files`	The content of the message.	`File`*	-
`isSelected`	Whether this message is the selected message in the parent `ChatMessageGroup`	`Boolean`	-
`executionMode`	Under which circumstances the node should be executed.	`ExecutionMode`	`Executable`
`compilationDigest`	A digest of the content, semantics and dependencies of the node.	`CompilationDigest`	`Executable`
`compilationMessages`	Messages generated while compiling the code.	`CompilationMessage`*	`Executable`
`executionDigest`	The `compilationDigest` of the node when it was last executed.	`CompilationDigest`	`Executable`
`executionDependencies`	The upstream dependencies of this node.	`ExecutionDependency`*	`Executable`
`executionDependants`	The downstream dependants of this node.	`ExecutionDependant`*	`Executable`
`executionTags`	Tags in the code which affect its execution.	`ExecutionTag`*	`Executable`
`executionCount`	A count of the number of times that the node has been executed.	`Integer`	`Executable`
`executionRequired`	Whether, and why, the code requires execution or re-execution.	`ExecutionRequired`	`Executable`
`executionStatus`	Status of the most recent, including any current, execution.	`ExecutionStatus`	`Executable`
`executionInstance`	The id of the kernel instance that performed the last execution.	`String`	`Executable`
`executionEnded`	The timestamp when the last execution ended.	`Timestamp`	`Executable`
`executionDuration`	Duration of the last execution.	`Duration`	`Executable`
`executionMessages`	Messages emitted while executing the node.	`ExecutionMessage`*	`Executable`
`id`	The identifier for this item.	`String`	`Entity`